Roughly 1/2 cup per gallon but always go with less and like Dave said. Mix, test mix.
You should always let the NSW mix for 24hrs to make sure it is well mixed and aerated.
So thats 4.66 ounces . a little over a half cup since a half cup in 4 ounces .
jwarren i have a postal scale that is good for 0.00 ounces .( hence i could wieght it out to 4.66 ounces ) do you think i could use this instead of a gram scale ?
You still want to test regardless. Different batches can be different and if you don't test you won't know. A refract is a good way to get accurate results for very little cost.
Lynn, that is the problem with using a cup to measure solids, cups are only good for measuring liquids. Always weigh solids and you will find that will hit the mark more frequent with the SG.
I have always weighed my salt and it comes out pretty consistant. I always test every batch, cause I have not been real impressed with IO the past couple of years.
I did a test with a friend that lives in North Dakota, in the mountains. He used my recipe for saltwater and came out at 1.021 consistantly. The only thing we could figure was altitude. I have tried to check this with others, but they had no idea what their altitude was.